158 lines · cpp
1//===- MapFile.cpp --------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements the -Map option. It shows lists in order and10// hierarchically the output sections, input sections, input files and11// symbol:12//13// Addr Off Size Out In Symbol14// - 00000015 10 .text15// - 0000000e 10 test.o:(.text)16// - 00000000 5 local17// - 00000000 5 f(int)18//19//===----------------------------------------------------------------------===//20 21#include "MapFile.h"22#include "InputElement.h"23#include "InputFiles.h"24#include "OutputSections.h"25#include "OutputSegment.h"26#include "Symbols.h"27#include "SyntheticSections.h"28#include "llvm/Support/Parallel.h"29#include "llvm/Support/raw_ostream.h"30 31using namespace llvm;32using namespace llvm::object;33using namespace lld;34using namespace lld::wasm;35 36using SymbolMapTy = DenseMap<const InputChunk *, SmallVector<Symbol *, 4>>;37 38// Print out the first three columns of a line.39static void writeHeader(raw_ostream &os, int64_t vma, uint64_t lma,40 uint64_t size) {41 // Not all entries in the map has a virtual memory address (e.g. functions)42 if (vma == -1)43 os << format(" - %8llx %8llx ", lma, size);44 else45 os << format("%8llx %8llx %8llx ", vma, lma, size);46}47 48// Returns a list of all symbols that we want to print out.49static std::vector<Symbol *> getSymbols() {50 std::vector<Symbol *> v;51 for (InputFile *file : ctx.objectFiles)52 for (Symbol *b : file->getSymbols())53 if (auto *dr = dyn_cast<Symbol>(b))54 if ((!isa<SectionSymbol>(dr)) && dr->isLive() &&55 (dr->getFile() == file))56 v.push_back(dr);57 return v;58}59 60// Returns a map from sections to their symbols.61static SymbolMapTy getSectionSyms(ArrayRef<Symbol *> syms) {62 SymbolMapTy ret;63 for (Symbol *dr : syms)64 ret[dr->getChunk()].push_back(dr);65 return ret;66}67 68// Construct a map from symbols to their stringified representations.69// Demangling symbols (which is what toString() does) is slow, so70// we do that in batch using parallel-for.71static DenseMap<Symbol *, std::string>72getSymbolStrings(ArrayRef<Symbol *> syms) {73 std::vector<std::string> str(syms.size());74 parallelFor(0, syms.size(), [&](size_t i) {75 raw_string_ostream os(str[i]);76 auto *chunk = syms[i]->getChunk();77 if (chunk == nullptr)78 return;79 uint64_t fileOffset = chunk->outputSec != nullptr80 ? chunk->outputSec->getOffset() + chunk->outSecOff81 : 0;82 uint64_t vma = -1;83 uint64_t size = 0;84 if (auto *DD = dyn_cast<DefinedData>(syms[i])) {85 vma = DD->getVA();86 size = DD->getSize();87 fileOffset += DD->value;88 }89 if (auto *DF = dyn_cast<DefinedFunction>(syms[i])) {90 size = DF->function->getSize();91 }92 writeHeader(os, vma, fileOffset, size);93 os.indent(16) << toString(*syms[i]);94 });95 96 DenseMap<Symbol *, std::string> ret;97 for (size_t i = 0, e = syms.size(); i < e; ++i)98 ret[syms[i]] = std::move(str[i]);99 return ret;100}101 102void lld::wasm::writeMapFile(ArrayRef<OutputSection *> outputSections) {103 if (ctx.arg.mapFile.empty())104 return;105 106 // Open a map file for writing.107 std::error_code ec;108 raw_fd_ostream os(ctx.arg.mapFile, ec, sys::fs::OF_None);109 if (ec) {110 error("cannot open " + ctx.arg.mapFile + ": " + ec.message());111 return;112 }113 114 // Collect symbol info that we want to print out.115 std::vector<Symbol *> syms = getSymbols();116 SymbolMapTy sectionSyms = getSectionSyms(syms);117 DenseMap<Symbol *, std::string> symStr = getSymbolStrings(syms);118 119 // Print out the header line.120 os << " Addr Off Size Out In Symbol\n";121 122 for (OutputSection *osec : outputSections) {123 writeHeader(os, -1, osec->getOffset(), osec->getSize());124 os << toString(*osec) << '\n';125 if (auto *code = dyn_cast<CodeSection>(osec)) {126 for (auto *chunk : code->functions) {127 writeHeader(os, -1, chunk->outputSec->getOffset() + chunk->outSecOff,128 chunk->getSize());129 os.indent(8) << toString(chunk) << '\n';130 for (Symbol *sym : sectionSyms[chunk])131 os << symStr[sym] << '\n';132 }133 } else if (auto *data = dyn_cast<DataSection>(osec)) {134 for (auto *oseg : data->segments) {135 writeHeader(os, oseg->startVA, data->getOffset() + oseg->sectionOffset,136 oseg->size);137 os << oseg->name << '\n';138 for (auto *chunk : oseg->inputSegments) {139 uint64_t offset =140 chunk->outputSec != nullptr141 ? chunk->outputSec->getOffset() + chunk->outSecOff142 : 0;143 writeHeader(os, chunk->getVA(), offset, chunk->getSize());144 os.indent(8) << toString(chunk) << '\n';145 for (Symbol *sym : sectionSyms[chunk])146 os << symStr[sym] << '\n';147 }148 }149 } else if (auto *globals = dyn_cast<GlobalSection>(osec)) {150 for (auto *global : globals->inputGlobals) {151 writeHeader(os, global->getAssignedIndex(), 0, 0);152 os.indent(8) << global->getName() << '\n';153 }154 }155 // TODO: other section/symbol types156 }157}158